Superiority of CDMA over GSM

[digitallogic 0]

This topic is to discuss how CDMA technology is superior to GSM technology, which is dominating the world mobile market.

From my opinion, CDMA has following advantages:

1) Superior Voice Clarity,

2) Higher Security due to inability to break the CDMA code uniquely assigned to him by operator.

Feel free to post your comments/views.

Edited December 3, 2010 by digitallogic

[rahuldixit2010 13]

I think CDMA is less secure as it is very easy to make clone phones on CDMA in comparison to GSM.

[Pulkit Gupta 47]

call rates i think is most imp point in this

[rajanmehta 4,056]

Voice Quality:

Always very superior in CDMA. Echoes, Voice distortion, non existent in CDMA. Simple life example. Voice quality in GSM somewhat similar to Microphone Recodring in PC. In CDMA it is almost equivalent to 320 kbps MP3 audio quality.

Coverage:

CDMA better equipped to reach inside building areas than GSM

Spectrum Efficienty:

For a given spectrum say 5 Mhz, CDMA can accomodate more subscribers than GSM.

Towers:

CDMA can serve more subscribers in one tower than GSM. Also physical distance reach of the tower is better than GSM.

[raccoon 53]

I beg to differ on some points, and am speaking from experience -

Voice Quality:

Always very superior in CDMA. Echoes, Voice distortion, non existent in CDMA. Simple life example. Voice quality in GSM somewhat similar to Microphone Recodring in PC. In CDMA it is almost equivalent to 320 kbps MP3 audio quality.

Have experienced echoes with CDMA many times. Happens even with both parties are on CDMA! Voice distortion can also happen. Technically, voice clarity drops with increasing load in the cell. In Pune, voice clarity on Uninor, Idea and Docomo (with good phones!) are comparable to better than RCDMA at least (no experience with other CDMA networks).

Coverage:

CDMA better equipped to reach inside building areas than GSM

This depends on frequency. Here, I have found that Idea (900 Mhz) in-building penetration is generally quite comparable to RCDMA. Others operating on the 1800 Mhz band will obviously not be comparable.

Spectrum Efficienty:

For a given spectrum say 5 Mhz, CDMA can accomodate more subscribers than GSM.

Towers:

CDMA can serve more subscribers in one tower than GSM. Also physical distance reach of the tower is better than GSM.

Can't argue with this. But GSM is also evolving...

Edited December 3, 2010 by raccoon

[parin 857]

Most irritating thing happens with GSM is searching network while Roaming,

But on CDMA u get connected instantly

Off course Voice quality is better than GSM Network

Also we can own cheaper highend handsets than GSM

[Greatest 55]

^^^ Parinbhai, cheaper CDMA highend handsets compared to their GSM counterparts are also available... you should be knowing this better..

[rbdhoot 11]

Everything is +ve with CDMA

Just One Minus point : PATENT with QUALCOMM

[rajeshkatiyar 3]

^^^ Parinbhai, cheaper CDMA highend handsets compared to their GSM counterparts are also available... you should be knowing this better..

Dear friend

with launch of 3 G everything will change. GSM will be having better voice quality and higher DATA speed

compared to 1x. TATA has limited towers and Reliance is cheat with bad connectivity,this is CDMA scene. Also

new generation Samsung GSM sets GURU 2152 has voice quality equal to CDMA . So the future is clear

[csmart 472]

qualcom patent killed CDMA at many places... besides, Europe/US always want their own standards. so CDMA is popular in US while GSM other countries. also qualcom patent for each handset sold, also shy away telcos.. in US, there is no patent charges on handsets...

everyone knows that CDMA has better penetration and other features compare to GSM but do not accept it.. the other problem with CDMA handset was unable to change SIM/service provider like GSM. now its possible with OMH, but its too late...

[Karthik R 246]

Advantages of CDMA are:

- It can accommodate more users per MHz of bandwidth than any other technology.

- It has no built-in limit to the number of concurrent users.

- CDMA is able to produce a reasonable call with lower signal (cell phone reception) levels.

- Its variable rate voice coders reduce the rate being transmitted when speaker is not talking, which allows the channel to be packed more efficiently.

- Has a well-defined path to higher data rates

- Increased cellular communications security.

- Extended reach - beneficial to rural users situated far from cells.

Disadvantages of CDMA include:

- Most technologies are patented and must be licensed from Qualcomm and due to its proprietary nature, all of CDMA's flaws are not known to the engineering community.

- Breathing of base stations, where coverage area shrinks under load. As the number of subscribers using a particular site goes up, the range of that site goes down.

- Manufacturers are often hesitant to release CDMA devices due to the smaller market, so features are sometimes late in coming to CDMA devices.

Advantages of GSM:

- Talktime is generally higher in GSM phones due to the pulse nature of transmission.

- The availability of Subscriber Identity Modules allows users to switch networks and handsets at will.

- GSM covers virtually all parts of the world so international roaming is not a problem.

- GSM's maturity means engineers cut their teeth on the technology, creating an unconscious preference.

Disadvantages of GSM:

- In GSM multiple users share the same bandwidth

- GSM has a fixed maximum cell site range of 35 km, which is imposed by technical limitations.

- Pulse nature of TDMA transmission used in 2G interferes with some electronics, especially certain audio amplifiers. 3G uses W-CDMA now (Dont know if the same applies to CDMA)

Which technology is the best for me?

When asking yourself which technology to choose between CDMA vs. GSM, first ask yourself the following questions:

1. Is international roaming important to me?

If you travel a lot to foreign countries, you might want to opt for a GSM phone for a better coverage.

2. Am I going to transfer a lot of data using the phone?

If you intend to use the phone for mobile web browsing, watching television or downloading MP3s, you might be better off with a CDMA phone. Currently, it offers the best data transfer speed with its EVDO technology and is the clear winner for now.

3. Do I plan to change phone often?

If you do, a GSM phone is best for you since you can swap the SIM card to a new device without having to re-enter your personal data.

[anandjm 3]

Not true. The baseline speech that is used for encoding is typically a 16bit linear or alaw/mulaw encoded speech at 8kHz. This is no way close to an MP3 audio quality even at 128kbps. So the quality of the speech signal used for coding in either CDMA or GSM will be similar. EVRC-B is likely to be better than the currently used EVRC/SMV in CDMA 1xRTT networks (CDMA for short). However EVRC/SMV at the highest bitrate is inferior to the enhanced fullrate GSM coders. Since the capacity of CDMA networks is higher, the quality of speech in general is likely to be higher for CDMA than for GSM networks when there is sufficient traffic since fewer packets are lost or corrupted. If there is little to no traffic, the quality in GSM is likely to be higher.

The main advantage of CDMA in my opinion is ability for graceful degradation and hence better capacity, better penetration through buildings, calls not being lost when there is transfer from one service station to another etc. Echoes has little to do with CDMA or GSM. Rather it has got to do with the Handset design and how the traffic is handled at the service stations.

Voice Quality:

Always very superior in CDMA. Echoes, Voice distortion, non existent in CDMA. Simple life example. Voice quality in GSM somewhat similar to Microphone Recodring in PC. In CDMA it is almost equivalent to 320 kbps MP3 audio quality.

Coverage:

CDMA better equipped to reach inside building areas than GSM

Spectrum Efficienty:

For a given spectrum say 5 Mhz, CDMA can accomodate more subscribers than GSM.

Towers:

CDMA can serve more subscribers in one tower than GSM. Also physical distance reach of the tower is better than GSM.

[abhisathe 8]

Hi Anand

Though I do not have a technical background, I could still understand the differentiation you made between CDMA and GSM. I have a few questions about both technologies. I will be glad if you could answer them.

1) Which technology will eventually prevail, CDMA or GSM?

2) I am a basic user of phone, with a basic phone requirement. Which technology is better in my case, CDMA or GSM?

3) Why do you receive bigger smses in pieces in CDMA, while in GSM you get through all at one go?

4) Why is Nokia not into CDMA handsets anymore?

Will be glad if you could answer these. tks.

[dr.faramroze 703]

In simple language, I explain in this way. Remembering 6 years back, I used to travel daily from Valsad to Mumbai thats 200 Kms. In this distance, I used to get disconnected only at a point in Gholvad and Bhayander. No hello i cant hear you kind of dialogues. Least call failures. Never seen any GSM carrier so versatile. On the highway NH8, there is full network absence only once. Even in jungles and fringle locations where BTS is far spaced. Interestingly, most CDMA phones work well on 2 signal bars.

US has one of the best CDMA networks in the world. Sprint, US cellular, Verizon and Bell dominate Cdma in North America. The only drawback faced is handset swapping is not as easy as a sim based gsm device. Cdma subscriber enjoys lower call rates than gsm. Unlocking and flashing a CDMA handset may not be everyone's cup of tea. Reprogramming CDMA is an expert's job.

CDMA could not do well except carriers offering cheap phones in India. CDMA Handset registering on carrier website should be made as easy as 123.

The day when manufacturers offer OMH sim based Windows, Android and Blackberry phones, it would be named revolution.

[Karthik R 246]

Revolution will be when the operators accept and activates foreign handsets without any hassle

[drmadhu 87]

GSM is Open source while CDMA patent by Qualcomm is minus point of CDMA.

[viper_in_blood 4]

my only guess is the operators r just not thinking tht thy r getting more subscribers but thy r worried abt the revenue loss by the non- sale of handset...which eventually will happen coz whn a subscriber dosent find satisfaction in his/her desired operator he will change whether or not the operator likes it or not....so even if the operator initially becomes successfull on hooking a subscriber to its services in the long run it will eventually harm his buisness....

[anandjm 3]

Sorry for the late reply.

1) Which technology will eventually prevail, CDMA or GSM?

GSM is on its way out being replaced by UMTS in most places.

2) I am a basic user of phone, with a basic phone requirement. Which technology is better in my case, CDMA or GSM?

This depends on the service provider, tariffs and signal coverage. For basic phone usage it all comes down to which provider is better (not CDMA or GSM).

For example, I moved to Tata Indicom because of its cheaper STD plans. I was a Hutch (now Vodafone) user initially when the prepaid tariff was better than Airtel. I changed to Tata because the number of STD calls increased. My postpaid bill on Vodafone was very high. It was cheaper for me to buy handsets and exploit the lower on-net STD tariffs of Tata which reduced my mobile bills by a factor of 10. I continue with Tata Indicom now just because I find it to have a better coverage in my area than any other GSM provider as well as lower costs.

3) Why do you receive bigger smses in pieces in CDMA, while in GSM you get through all at one go?

The SMS character length is 160. This is including the callback number and some other details. Anything less than this or more is likely to be related to the handset or the service provider. I do not think it has got to do with the CDMA vs GSM question.

4) Why is Nokia not into CDMA handsets anymore?

AFAIK Nokia still manufactures CDMA handsets but not too many. Their main focus is on GSM as their top markets are in Europe and Asia. They have a lot of patents related to GSM because of which their profit margins are higher. Qualcomm holds a significant patent portfolio as far as CDMA is concerned. Even in W-CDMA used in UMTS networks some report as much as 47% of the relevant patents as belonging to Qualcomm.

I hope this answers your questions well enough.

[carbinem4 2]

Advantages of CDMA are:

- It can accommodate more users per MHz of bandwidth than any other technology.

- It has no built-in limit to the number of concurrent users.

- CDMA is able to produce a reasonable call with lower signal (cell phone reception) levels.

- Its variable rate voice coders reduce the rate being transmitted when speaker is not talking, which allows the channel to be packed more efficiently.

- Has a well-defined path to higher data rates

- Increased cellular communications security.

- Extended reach - beneficial to rural users situated far from cells.

Disadvantages of CDMA include:

- Most technologies are patented and must be licensed from Qualcomm and due to its proprietary nature, all of CDMA's flaws are not known to the engineering community.

- Breathing of base stations, where coverage area shrinks under load. As the number of subscribers using a particular site goes up, the range of that site goes down.

- Manufacturers are often hesitant to release CDMA devices due to the smaller market, so features are sometimes late in coming to CDMA devices.

Advantages of GSM:

- Talktime is generally higher in GSM phones due to the pulse nature of transmission.

- The availability of Subscriber Identity Modules allows users to switch networks and handsets at will.

- GSM covers virtually all parts of the world so international roaming is not a problem.

- GSM's maturity means engineers cut their teeth on the technology, creating an unconscious preference.

Disadvantages of GSM:

- In GSM multiple users share the same bandwidth

- GSM has a fixed maximum cell site range of 35 km, which is imposed by technical limitations.

- Pulse nature of TDMA transmission used in 2G interferes with some electronics, especially certain audio amplifiers. 3G uses W-CDMA now (Dont know if the same applies to CDMA)

Which technology is the best for me?

When asking yourself which technology to choose between CDMA vs. GSM, first ask yourself the following questions:

1. Is international roaming important to me?

If you travel a lot to foreign countries, you might want to opt for a GSM phone for a better coverage.

2. Am I going to transfer a lot of data using the phone?

If you intend to use the phone for mobile web browsing, watching television or downloading MP3s, you might be better off with a CDMA phone. Currently, it offers the best data transfer speed with its EVDO technology and is the clear winner for now.

3. Do I plan to change phone often?

If you do, a GSM phone is best for you since you can swap the SIM card to a new device without having to re-enter your personal data.

It seems somebody copied this from Wikipedia..... HE HE HE

[ipkonfig 10]

I always come across forum posts highlighting the superior voice clarity of CDMA. However, I am much more satisfied with GSM in that department. Has it got anything to do with the low end CDMA phone I use? (LG RD 3500)

[Karthik R 246]

@carbinem4

Wikipedia, some part, Wikileaks? hell no!

The coverage of a CDMA tower is equivalent to those of 4 GSM ones - These findings and claims are obivious and are made since long and asks for no discovery on my part. I pieced them from the www with few personal remarks. Answered to the query, thats it

[coolblue 10]

Advantages of CDMA are:

- It can accommodate more users per MHz of bandwidth than any other technology.

- It has no built-in limit to the number of concurrent users.

- CDMA is able to produce a reasonable call with lower signal (cell phone reception) levels.

- Its variable rate voice coders reduce the rate being transmitted when speaker is not talking, which allows the channel to be packed more efficiently.

- Has a well-defined path to higher data rates

- Increased cellular communications security.

- Extended reach - beneficial to rural users situated far from cells.

Disadvantages of CDMA include:

- Most technologies are patented and must be licensed from Qualcomm and due to its proprietary nature, all of CDMA's flaws are not known to the engineering community.

- Breathing of base stations, where coverage area shrinks under load. As the number of subscribers using a particular site goes up, the range of that site goes down.

- Manufacturers are often hesitant to release CDMA devices due to the smaller market, so features are sometimes late in coming to CDMA devices.

Advantages of GSM:

- Talktime is generally higher in GSM phones due to the pulse nature of transmission.

- The availability of Subscriber Identity Modules allows users to switch networks and handsets at will.

- GSM covers virtually all parts of the world so international roaming is not a problem.

- GSM's maturity means engineers cut their teeth on the technology, creating an unconscious preference.

Disadvantages of GSM:

- In GSM multiple users share the same bandwidth

- GSM has a fixed maximum cell site range of 35 km, which is imposed by technical limitations.

- Pulse nature of TDMA transmission used in 2G interferes with some electronics, especially certain audio amplifiers. 3G uses W-CDMA now (Dont know if the same applies to CDMA)

Which technology is the best for me?

When asking yourself which technology to choose between CDMA vs. GSM, first ask yourself the following questions:

1. Is international roaming important to me?

If you travel a lot to foreign countries, you might want to opt for a GSM phone for a better coverage.

2. Am I going to transfer a lot of data using the phone?

If you intend to use the phone for mobile web browsing, watching television or downloading MP3s, you might be better off with a CDMA phone. Currently, it offers the best data transfer speed with its EVDO technology and is the clear winner for now.

3. Do I plan to change phone often?

If you do, a GSM phone is best for you since you can swap the SIM card to a new device without having to re-enter your personal data.

The last point is somewhat wrong as CDMA too now have SIM Cards and now have open market phones so you can use that handset for any of the CDMA operator in India. The problem is that there is no variety in handsets available. For example, you wish to buy a touchscreen gsm phone you have so many options but in CDMA you have to contain Samsung Corby or else there is one model available in HTC.

[Karthik R 246]

The problem is that there is no variety in handsets available. For example, you wish to buy a touchscreen gsm phone you have so many options but in CDMA you have to contain Samsung Corby or else there is one model available in HTC.

You missed out official LG cookie ZIP and Reliance's android powered Samsung Galaxy i899 (overpriced but EVDO works) and the programmable foreign handsets Yup, CDMA users are not pampered with choices as is the case with GSM.